This invention relates generally to controlled environment agriculture apparatus and facilities more specifically to such apparatus and facilities modularized to facilitate transportability to or between installation and use sites.
As described in greater detail in copending application Ser. No. 889,965 filed Mar. 24, 1978 now U.S. Pat. No. 4,163,342 by Fogg et al, controlled environment agriculture is the cultivation of vegetable, ornamental and other plants in an enclosure within which all those environmental factors which are generally recognized as influencing plant growth, maturation and productivity, are systematically time programmed and carefully controlled. As also explained in that application, such environmental control technology may most effectively be implemented using a nutrient film technique in which the plant roots are contained in sloped troughs or gullies through which a low-volume nutrient solution flow is effected.
One of the controlled environment agriculture (CEA) problem areas to which the invention of the aforementioned Fogg et al application was directed is that of maintaining good uniformity of distribution of the supply of air to and about the plants being cultivated, throughout the CEA enclosure. With conventional air supply and distribution arrangements there normally will exist substantial inequalities of temperature and areas of stagnation of air, neither of which is conducive to optimized plant growth. These problems are compounded by the relatively close concentration of plants required for efficient utilization of the CEA enclosure space, and by the substantial infrared energy output of the high intensity lamps which are the preferred source of illumination.
To minimize these problems and to assure equalized distribution of air supply to all plants within the CEA enclosure volume, the aforesaid Fogg et al application discloses a number of alternative embodiments of air distribution control means. The present invention is directed to another such means, similar in basic purpose and operation to the air distribution control of the Fogg et al application but affording significantly better adaptability to use in transportable facilities, i.e., CEA facilities which can readily be shipped to and installed in remote locations or removed between such locations.
To facilitate such transportability, the CEA facilities of the invention are modularized by division into one or more plant growth modules and a service module which contains or carries such accessory and support equipment as the air conditioning units and the nutrient storage and supply system. The plant growth module or modules and the service module may conveniently be interconnected during installation using quick-disconnect devices in the various supply and return lines of the nutrient system, and with similarly disconnectable couplings between the air conditioning units in the service module and the air distribution and return systems in the plant growth modules. In accordance with the invention these air return systems are incorporated into plant support rack assemblies which are movably housed within the plant growth modules, and the module structures themselves require only the simplest of air fittings thus greatly facilitating module transportability and installation.
The modularized facility of the present invention is not limited in applicability to use in installations requiring transportability, but may also be advantageous for fixed installations as well. In such installations the modularized design enhances the adaptability of the facility to specific local needs, as by enabling its sizing to achieve desired output objectives and configuration of its plant support systems for optimized growth of the specific vegetables or other crops necessary to satisfy nutritional requirements or dietary preferences of the particular locality in which the facility is sited. Reconfiguration of the facility to adapt it to crop changes from season to season or locality to locality is similarly easily accomplished without modification of the basic module structure.